A new strategy for the optimal design of a distillation column is developed. Major difficulties in the optimal design of a distillation column are such facts that the number of stages is discrete and the total number of model-ing equations varies with the number of stages. In this study, Two-Tier Approach in which both rigorous and reduced model exist is applied to solve such difficulties. Reduced model is composed of equations only and the numbers of stages in the column sections are treated as real variables. In these respects, optimization calculation is performed with reduced model and rigorous simulation follows on the basis of the results obtained. The recursive execution of the above mentioned optimization and simulation step results in the optimal design of distillation column. ODDS(Optimal Design of Distillation System)system which implemented Two-Trier Approach is developed. ODDS system is proved to be effective by case studies though not perfect yet.

This study is to predict adsorption equilibrium data for binary gas mixture systems using the vacancy solution model(VSM). The single component adsorption isotherms of propane and n-butane on a 5A molecular sieves(Davison C-625) were determined experimentally and from these isotherms the parameters in a single component adsorption isotherm equation by the vacancy solution model()were calculated. A nonlinear regression method and an optimization method were employed in the calculation of the parameters. The parameters were then used in the prediction of the binary gas mixture adsorption equilibrium curve through a trial-and-error method. The experimental mixed-gas adsorption data for varying composition of propane-n-butane mixture were in good agreement with the predicted equilibrium curve based on the VSM.

Design methods of composition control loops of a distillation column, which give small interaction effects, were proposed for two different cases, single- and dual-composition controls, through steady-state simulation study. In case of the single-composition control, the operating conditions could be catagorized into two different ones, on one hand where the desired product is completely recovered without loss and on the other hand where a certain amount of the desired product is allowed to emanate through the other end of the column. Different control loops were suggested depending on the operating conditions for each case. By extending the results of the single-composition controls, design methods for dual-composition control loops were also proposed. In this case, the operating conditions could be divided into four different ones and an appropriate control loop which give minimum interaction effects was suggested for each case.

Catalytic conversions of propylene, propane and n-pentane to aromatic hydrocarbons over gallium-substituted silicalites were studied. Temperature-programmed desorptions(TPD)with ammonia and propylene and intracrystalline effective diffusivity measurements of reactants were carried out to investigate the catalytic properties of gallozeolites for each reaction. The selectivity for aromatic compounds was higher over the gallium-substituted catalysts than over HZSM-5 and the effect of gallium on the selectivity for aromatic compounds was found to be in the order of propane>n-pentane>propylene. It was explained that the higher selectivity for aromatic compounds over gallozeolites might be attributed to great adsorption strengths of olefins and high effective diffusivities of lower hydro-carbons.

The compression characteristics of the flocculated granule with polymeric binders were investigated. To evaluate quantitatively the compressibility and reassertion(postpressing growth) of the granular bed, real time data acquisition system was specially designed. Nearly continuous pressure-density curves clearly showed the dominating volume-reduction mechanisms during the entire compression and decompression process and showed the effects of the binder characteristics, granule size.

Kinetics of dehydration and reductions were studied by TGA(thermogravimetric analysis)method. The mechanism for dehydration and reduction of were elucidated. Also, reaction orders, activation energies and frequency factors were obtained in each step. Experiments were done between ambient temp. and , and the heating rate was kept as /min. Consequently, and were obviously appeared as interme-diates in overall reaction path. And reduction of was 2.60 and 1.0, respectively. Also, the frequency factor and activation energy were and 50kcal/gmol, respectively. In the dehydration step, reaction order, frequency factor and activation energy were 0.46, and 26.2kcal/gmol, respectively.

A product formation model including growth associated and maintenance terms is developed for the growth of mammalian cells under Perfusion Chemostat(PC) cultivation. Two parameters in this model, growth associated term, , and maintenance factor, , are estimated for the production of tPA, EPO and pro-UK, and fitting these data with correlation factors of 0.90 to 0.93 for each case. It turned out that essential factors for cell growth, such as shear stress and dissolved oxygen tension play important role with respect to productivity, showing optimal values of 30-40% of dissolved oxygen tension and 20-50rpm of agitation speed for the production of EPO from recombinat CHO cells.

The effect of stirring speed and rate on the mesophase formation during the heat treatment of Naphtha tar pitch at was investigated. The mesophase content was found to increase with agitator Rey-nolds number and superficial velocity of gas. However, the mesophase content decreased slightly when the agitator Reynolds number and superficial velocity of gas were above 24.5, 31.4cm/min respectively. It was also found that the mesophase was deformed by stirring and needle like structures aligned to stirring direction were observed with increasing agitator Reynolds number. The degree of alignment caused by the stirring depend-ed on the stirring speed. The mesophase deformed was rearranged to the spheres by annealing.

In the present works the porous structure of silica particle was modified to the more open-packed net-work of particles to provide greater porosity and pore radius by transfering nitric acid from the continuous phase of TBP(tributyl phosphate)-ethanol containing nitric acid into the drops of sodium silicate aqueous solution, where the soluble silica was transformed into active silica, simultaneously polymerized to the porous network of silica particles. The structural characteristics of silica were improved to have large pore radius of , high pore volume of and specific surface area of by increasing the diameter of primary particle and the rate of production of active silica. The resulting structural characteristics were compared to the particle formation model bas-ed on the mass transfer rate of nitric acid and the polymerization kinetics of soluble silica, and the systematic research results presented valuable information about the mechanism of particle formation and the porous structure of silica.

and catalysts were prepared by precipitation from the solution of zirconium oxychloride followed by modification with phosphoric acid and boric acid, respectively. The characterization of prepared catalysts was examined by infrared spectra, X-ray diffraction and differential thermal analysis. On the basis of the results obtained from X-ray diffraction and DTA for modified with acids, the transition temperature from amorphous to tetragonal phase was high by and the specific surface increased by about , as compared with pure . The acid strength of modified catalysts increased by 2.6-5.2 unit as Ho scale.

A series of supported sulfided Co-Mo/ catalysts of different cobalt contents were tested in a fixed bed flow reactor for the hydrodesulfurization of dibenzothiophene(DBT)dissolved in n-heptane. Reaction temperatures were between 533K and 537K, and total reaction pressures were from 20 to . Most of the products observed were biphenyl and cyclohexylbenzene, and only negligible amount of bicyclohexyl and tetrahydrodibenzothiophene were detected. The catalytic activities with different cobalt contents were shown to be maximum in the range of R=Co/(Co+Mo)=0.2-0.3 under standard condition. The reaction was first order with respect to DBT concentration, and the average activation energy was 23.4kcal/gmole.

The highly crystalline zirconium bis(monohydrogen orthophosphate)monohydrate[; hereinafter -ZrP]was synthesized. Co(II)-exchanged -ZrP[hereinafter Co(II) -ZrP]was prepared by the ion-exchange method using aqueous cobalt(II) acetate solution, and its characteristics were studied. Cobalt(II) cations were ion-ex-changed into the proton sites of -ZrP and as the result of cobalt ion-exchange a new phase of was formed. And the interlayer spacing of Co(II) -ZrP was expanded from of-ZrP to . The ion-exchanged cobalt(II) cations seemed to be stabilized in the interlayer spacings of -ZrP by forming the water coordinated complexes as a high spin state of cobalt. Four molecules of water could be ligated into cobalt(II) cations and these seemed to be easily exchanged with the polar ligand such as an ammonia.

Chromatographic technique was used to determine mass transfer parameters of large-pore particles in packed columns. Particle and column tortuosity factors were determined by the arrested-flow gas chromatography, and adsorption equilibrium constant by the arrested-flow gas chromatography and the continuous-flow gas chromatography. Extraparticle and intraparticle diffusivities could be more effectively determined by the arrested-flow gas chromatography, but adsorption equilibrium constant more effectively by the continuous-flow gas chromatography.

As an ultrafiltration membrane material, novel aromatic copoly(amide-ester)(ACAE) was synthesized by low temperature solution polycondensation. This copolymer was characterized by IR, EA, X-ray, TGA thermo-grams. Membranes were cast from polymer solution consisting of ACAE, one of solvents from the group of N, N-dimeth-ylacetamide(DMAc), N-methyl-2-pyrrolidone(NMP) containing lithium chloride. The permeation characteristics were investigated with regard to the effect of membrane preparation variables such as evaporation process, the composition of mixed solvents used as gelation medium and of permeation conditions such as feed concentration, operating pres-sure, molecular weight of the feed solution. As the performance test, pure water flux, solute rejection, molecular weight cut off of membranes from different preparation condition were also investigated with the aid of scanning electron microscope.

Here is reported a theoretical prediction of the onset time for thermal convection in a horizontal porous layer for the case of ramp heating from below. From the stability analysis based on the propagation theory under Brinkman's model the dimensionless critical time to mark convection is predicted as follows: In comparison of the above prediction with extant results by amplification theory, it is seen that for a given Darcy number the initiated convection is amplified to observable magnitude around the time 4 . Additionally, some feature of the momentum boundary layer in thermal convection is discussed in connection with the thermal penetration depth.